A long sought after goal in the floral industry has been the extension of the shelf life of cut floral produce during post-harvest shipment. Inherent in any such endeavor are the requirements to manage both temperature and humidity within containers in which the floral produce is stored and shipped.
Temperature control may require either cooling, or more rarely warming of produce post harvest. Cooling may be initially effected by the introduction of ice, cold water, or cold air. The initial cooling of produce may with equal facility be effected by the packing of the floral produce with ice, ice slurry, or cold water, or other cooling methods known to those of ordinary skill in the art.
One shipping container which readily adapts itself to a vacuum process for using cold air cooling is taught by Stollberg in U.S. Pat. No. 4, 176,745. As taught by the '745 patent, a shipping container comprising a tray and separable cover sections are provided with closure flaps on both the tray and cover sections. When the cover is in place on the tray, the two flaps, being in registry, provide communication between the interior of the shipping container and the ambient temperature. Such communication may then be used to withdraw, by vacuum, the relatively warm air from inside the container having stored within it floral produce. The relatively warm air is replaced with relatively cool or cold air from within a refrigerated storage facility.
The container taught by '745 is, in many respects, typical of container of containers in general use in the floral industry. Referring now to FIGS. 5 and 6 of that reference, it will be appreciated that the tray and cover taught therein are formed of a single piece of cut and formed corrugated cardboard which has been preformed by cutting and creasing so as to enable its assembly into its final form. '745 teaches, for instance at Column 2, lines 65-67, that "any suitable expedient such as glue, staples, etc., may be employed to secure the flaps to the side walls". From the study of those figures, it will be apparent that the container taught by Stollberg will be prone to leakage of any water from within the container. By way of example, but not limitation, such water or other fluids may have been injected in the container in the form of cold water, ice slurry, melted ice, or the water given off by respiration or decomposition of the floral produce stored within.
In addition to the maintenance of a reasonably optimal storage and shipping temperature, the attainment and maintenance of a reasonably optimal humidity or moisture level is also of critical importance to the prolonged storage and shelf life of most floral produce, indeed of most fresh produce of all kinds. To this end, a number of methodologies have been adapted to retain moisture about produce. A common means to this end is the providing, within a shipping container, of a moisture barrier. One such barrier is taught in U.S. Pat. No. 5,379,549 to Carcich, et al. As taught by Carcich, cut produce as well as a moisture retention block is encompassed in a moisture barrier for maintaining the proper humidity of the floral produce stored within. This moisture barrier, comprising for instance a polyethylene sheet bag, is then enclosed in a box, preferably of corrugated fiber board construction, which is in turn sealed.
A problem encountered by the use of commonly available plastic bags, for instance polyethylene sheet bags, occurs when the floral produce being stored within contains projections such a spines or thorns which might tend to puncture or tear the bag into which the floral produce is inserted. Depending upon the degree to which the integrity of the moisture barrier is compromised, humidity and liquid retention may be degraded or lost entirely.
The moisture barrier, if undamaged, could serve to retain water within the shipping container. However, from the previous discussion it will be apparent that the storage of many produce types within plastic bags renders them extremely susceptible to damage and hence leakage.
Some floral produce has been shipped in insulated containers to further prolong its shelf life by maintaining a desired temperature for extended periods of time. Such insulated containers have taken the form of plastic structures formed of, for instance, expanded polystyrene bead foam. Such foam containers are exceptionally prone to damage during shipment so another alternative has been to further package the foam container within, for instance, a corrugated cardboard container to minimize damage to the foam containers. This alternative has the disadvantage of requiring a significant investment in shipping containers per quality of floral produce shipped.
What is needed is a low cost, insulated container for the storage of floral produce which is capable of extending the storage and shelf life of the produce stored within by thermally insulating the produce form the ambient temperature. Such a container should not only be in and of itself water resistant, but should be capable of retaining within a sufficient quantity of water without leakage. Containers should be capable of assembly using commonly found assembly methods and should be capable of being compactly stored and shipped prior to use by the grower or packer.